More mypy (#612)

* remove type comment where type is annotated
* move function tests
* remove six from tests
* add none annotations
* add more types
* change mock (so that mypy understands it)

test/test_functions/test_function_buzzer.py

@@ -0,0 +1,55 @@
+import pytest
+
+from escpos import printer
+from escpos.constants import BUZZER
+
+
+def test_buzzer_function_with_default_params() -> None:
+    instance = printer.Dummy()
+    instance.buzzer()
+    expected = BUZZER + bytes((2, 4))
+    assert instance.output == expected
+
+
+@pytest.mark.parametrize(
+    "times, duration",
+    [
+        [1, 1],
+        [2, 2],
+        [3, 3],
+        [4, 4],
+        [5, 5],
+        [6, 6],
+        [7, 7],
+        [8, 8],
+        [9, 9],
+    ],
+)
+def test_buzzer_function(times: int, duration: int) -> None:
+    instance = printer.Dummy()
+    instance.buzzer(times, duration)
+    expected = BUZZER + bytes((times, duration))
+    assert instance.output == expected
+
+
+@pytest.mark.parametrize(
+    "times, duration, expected_message",
+    [
+        [0, 0, "times must be between 1 and 9"],
+        [-1, 0, "times must be between 1 and 9"],
+        [10, 0, "times must be between 1 and 9"],
+        [11, 0, "times must be between 1 and 9"],
+        [3, 0, "duration must be between 1 and 9"],
+        [3, -1, "duration must be between 1 and 9"],
+        [3, 10, "duration must be between 1 and 9"],
+        [3, 11, "duration must be between 1 and 9"],
+    ],
+)
+def test_buzzer_fuction_with_outrange_values(
+    times: int, duration: int, expected_message: str
+) -> None:
+    instance = printer.Dummy()
+    with pytest.raises(ValueError) as e:
+        instance.buzzer(times, duration)
+
+    assert str(e.value) == expected_message